Cineradiographic studies of the normal cervical spine.

By considering the cervical spine as several segments with relatively different motions, an understanding of the total possible motions of the cervical spine can be more easily attained. Reversal of the cervical lordosis is a normal part of the flexion action and can result from positioning of the patient for radiographic studies. The effect of standing or sitting postures, and methods of initiating flexion of the neck should be considered in the evaluation of routine flexion and extension studies. Evaluation of individual cervical segments may be accomplished by the use of different methods of initiating flexion.